In the end, none of Sen. John Ensign’s colleagues came to hear his farewell speech on Monday. The Nevada Republican stood mostly alone in the empty chamber – a familiar feeling for him over the past two years since a sex scandal threw him headlong into an embarrassing ethics investigation and derailed his promising political career.

Overshadowed by news of Osama bin Laden’s death, Ensign was candid in assessing his own downfall, explaining that he had fallen victim to the same character flaws – arrogance and self-importance – that had ruined other Senate colleagues.

“When one takes a position of leadership, this is a very real danger of getting caught up in the hype surrounding that status. Oftentimes, the more power and prestige a person achieves, the more arrogant a person can become,” Ensign said.

“As easy as it was for me to view this in other people, unfortunately, I was blind to how arrogant and self-centered that I had become. I did not recognize that – that I thought mostly of myself.”

Ensign is expected to resign from office on Tuesday, a day before he was scheduled to testify before the Senate Ethics Committee in an investigation into whether he violated Senate rules during his affair with Cindy Hampton, a former campaign aide. Nevada Gov. Brian Sandoval has appointed Rep. Dean Heller (R-Nev.) to succeed Ensign.

Ensign used his final floor speech to thank God, his staffers and supporters; to apologize to his wife and children, as well as his Nevada seatmate, Democratic Senate Majority Leader Harry Reid; and to tout his legislative accomplishments, including an expansion of the Nevada parks system, protection of Lake Tahoe and education reform.

But Ensign also warned his fellow senators – none of whom joined him on the Senate floor – not to surround themselves with “yes” men.

“My caution to all of my colleagues,” he said, “is to surround yourself with people who will be honest with you about how you really are and what you are becoming, and then make them promise to not hold back, no matter how much you may try to prevent them, from telling you the truth.”

Had Ensign taken his own advice, he said, he would not have judged two of his colleagues who were caught up in their own ethics scandals: former Sen. Larry Craig (R-Idaho) and the late Sen. Ted Stevens (R-Alaska).

“Following Larry’s admission and Ted’s guilty verdict, I, too, believed in the power of my leadership position and I called on both of them to resign,” said Ensign, who was chairman of the National Republican Senatorial Committee at the time. “I sincerely struggled with these decisions afterward, so much so that I went to each of them a few weeks afterward and admitted what I did was wrong and I asked both of them for forgiveness.”

They did, and Ensign said Craig was one of the first people to call and express his support after the Nevada senator admitted his affair.

“The purpose of me speaking about this is to humbly show that in life, a person understands mercy a lot more when they need it and when it is shown to them,” Ensign said. “Again, this is a hard lesson that I have had to learn, but I hope that can now show mercy to people who come into my life who truly need it.”

Some had warned Ensign not to mention God in his farewell speech, noting that it could appear hypocritical “because of his own personal failings.” But Ensign was undeterred.

“I would argue that I have not mentioned him enough,” he said. “I’m glad that the Lord not only forgives, but he actually likes it when we give him thanks. So, Lord, thank you for all that you’ve done in my life.

“I hope that I can do better in the future. I hope that I can learn to love you with all of my heart, soul and strength and to love others as myself,” Ensign added. “My colleagues, I bid you farewell. Know that you will all be in my prayers.”